A Mirror for Observers

In their attitude towards the Planet Earth, the Martians had long been divided into two camps: the Observers, benevolent meddlers in human affairs; & the rebellious Abdicators, who sought the Earth's collapse. But it wasn't until the extraordinary matter of the Earth-Boy, Angelo Pontevecchio, that the enmity between these two factions came to a definite head.
It started as a contest of wills, waged between two opposing Martians for the soul of a single human child. Before the end, it threatened all life on both Earth & Mars.